Buckingham Palace says Queen Elizabeth's husband has suffered a minor ankle injury in a carriage-driving accident at his estate in Windsor. The palace says Prince Philip did not need hospital treatment when his carriage hit a tree stump Friday morning and was “out and about as normal” this afternoon. However a female groom, who was with the duke at the time, did have to go to hospital to check out an elbow injury. The ponies used to drive the carriage were unharmed. The 88-year-old Duke of Edinburgh, an experienced carriage driver, was forced to miss engagements last year because of a back injury sustained while practicing the sport. Earlier this month, Camilla, the wife of his son Prince Charles, broke her left leg while hiking in Scotland.